Round 1 - Referee Yves Lavigne in charge of this welterweight matchup. Kim lands an early low kick as the southpaws measure distance. Pierson moves into the clinch and pushes Kim against the cage. THey break, and both fighters trade low kicks. Pierson catches one and tries to counter up top but Kim shakes it off. Kim using powerful kicks early, but Pierson answering and mixing in punches as well. Pierson catches another kick but can't deliver the counter. Kim land a stiff left. A right follows. Good punches from Kim. Kim keeps throwing a jumping front kick, but Pierson is ready each time. Kim seems to be managing the range well, but Pierson is not backing down. Final minute. Kim latches onto a guillotine on the feet. Pierson breaks free, but he finds himself hiptossed to the floor. Pierson does a great job of transitioning from being thrown and leaps onto the back. Great finish for Pierson. Tight round with the late work from Pierson, but MMAjunkie.com going to lean slightly toward Kim, 10-9.

Round 2 - Spirited exchanges to open, but it's Kim again who seems to be getting just a little better of the flurries. They clinch up against the cage, but Kim pulls off the cage without taking damage. Kim keeps chopping away at the lead leg, and Pierson's counterpunches are just a little short. Pierson ties it up again, but Kim scurries away. Traded low kicks. Pierson short again on a combination, and Kim lands another two solid blows. Kim looks for the throw, but it's not there, and Pierson looks to move to the back. He doesn't capitalize, and Kim pulls away. Final minute. Pierson lands a nice leg kick that sees Kim stagger a bit, but it's definitely Kim who is just slightly better. Jumping front kick wobbles Pierson, and he hits the deck. Kim rushes in to finish but won't have time. He's punching away, but Pierson survives until the bell. He staggers to his corner, and MMAjunkie.com gives Kim the frame, 10-9.

Round 3 - Pierson looks at least a little bit recovered, and Kim isn't overly aggressive to open. He does move in behind a few strikes, but there's nothing there. Kim continues to work kicks from various angles. Kim ducks in for a quick takedown, and it comes very easily. He tries to advance position on the floor, but Pierson scrambles up to his feet. Kim stays tight and uses a bodylock to bring the fight again to the floor. Pierson scrambles to full guard halfway into the round. Kim tries to posture, but Pierson keeps him tight. Kim stands, allowing him to advance a little when he returns, but Lavigne doesn't see enough action and calls for a restart. Kim continues to work the front kick. Pierson looking for a homerun shot in the final minute. His arms look weary as he reaches out. Kim scores with a jab and a superman punch. Pierson answers, but Kim scores with a knee in the closing seconds. Bell sounds, and MMAjunkie.com sees the final round for Kim, 10-9, giving him the fight 30-27. Dong Hyun Kim def. Sean Pierson via unanimous decision (30-27, 30-27, 30-27).